080223 It sounds like either the saves aren't in the folder the game is currently reading, or the saves aren't named correctly. For the former, the correct folder can change for various reasons, so please check the location of the saves against the one you see in-game, as described here:
https://sims4.crinrict.com/eng/2018/07/how-to-find-your-user-folder/
The full path needs to match, everything from the drive letter to "The Sims 4."
If the saves are in the correct folder, please post a screenshot of the contents of that folder, as in, I'd like to see the save names and dates. Include the address bar, above the list of files, in the screenshot.